An LED is useful because when a current passes through it, it gives out light.
If only 1 option is correct then it is (D)
All the others can also make one component negative, all depends how u measured the angle.
all the best
<span>The statement is TRUE. Water does have potential energy at the top of a slope. The reason why is that potential energy is energy possessed by a body based on its position relative to a zero point. In this case, water at the top of the slope is at an elevation above ground (zero point). The energy is not kinetic (moving) energy since the water is not moving.</span>